I have a Flex App written in Go and React that is deployed to Google App engine. I would like it to interact with a MySql Database (2nd generation) on Google Cloud over a Unix socket. I believe the issue lies with the Go server not launching/responding to requests (see below for justification). The App is located at https://haveibeenexploited.appspot.com/
The project is simple. I have two routes in my Server:
server.go
package main
import (
"net/http"
"searchcontract"
)
func main() {
http.Handle("/", http.FileServer(http.Dir("./app/build")))
http.HandleFunc("/search", searchcontract.SearchContract)
http.ListenAndServe(":8080", nil)
}
The second route ("/search") is activated when a user hits the search button. Ideal behavior should return a row specifying the exploits available for the given "contract address" which React writes out to the screen. searchcontract/searchcontract.go
//SearchContract is a handler that queries the DB for compromised contracts.
func SearchContract(w http.ResponseWriter, r *http.Request) {
var contractName contractID //Used for parsing in contractName
queryResult := getRow(&contractName.Name)
w.WriteHeader(200)
json.NewEncoder(w).Encode(queryResult)
}
//processRow queries the DB for a contract with ID value of name.
func getRow(contractName *string) *ContractVulnerabilityInfo {
var storage ContractVulnerabilityInfo //stores row to encode
//Login to database
...
scanErr := db.QueryRow("SELECT * FROM contracts WHERE ContractAddress=?;", &contractName).Scan(&storage.ContractAddress, &storage.IntegerOverflow, &storage.IntegerUnderflow, &storage.DOS, &storage.ExceptionState, &storage.ExternalCall, &storage.ExternalCallFixed, &storage.MultipleCalls, &storage.DelegateCall, &storage.PredictableEnv, &storage.TxOrigin, &storage.EtherWithdrawal, &storage.StateChange, &storage.UnprotectedSelfdestruct, &storage.UncheckedCall)
...
return &storage
}
My app.yaml
file should allow me to deploy this flex app and does:
runtime: go1.12
env: flex
handlers:
- url: /.*
script: _server # my server.go file handles all endpoints
automatic_scaling:
max_num_instances: 1
resources:
cpu: 1
memory_gb: 0.5
disk_size_gb: 10
env_variables:
# user:password@unix(/cloudsql/INSTANCE_CONNECTION_NAME)/dbname
MYSQL_CONNECTION: root:root@unix(/cloudsql/haveibeenexploited:us-west1:hibe)/mythril
# https://cloud.google.com/sql/docs/mysql/connect-app-engine
beta_settings:
cloud_sql_instances: haveibeenexploited:us-west1:hibe
I am able to query the database successfully on localhost.Localhost correctly shows address
However, whenever I try to implement and push to AppEngine, when I query something that should be in the database, it does not show up in the remote App! App Engine does not show address in database. Furthermore, I get a status code of '0' returned, which indicates to me that the server function isn't even being called at all ('200' is what I expect if successful or some other error message.').
Summary
I can't wrap my head around this bug. What should work locally should work remotely. Also, I can't debug this app probably because Stackdriver does not support flex apps and the devserver Google Cloud provides does not support Go Apps.
I believe the primary issue is with Go not speaking to the React element correctly or the routing not being taken care of appropriately.
1) The problem does not lie with MySql connection/database access - I changed my route to only be one page, turned off React, and included a hardcoded query. The result on localhost. The result on App Engine
2) There is an issue in either a) my routing or b) the interaction between React and Go. 3) Go seems to start correctly... at least when React is not started.
Any help is appreciated.
EDIT I believe that the go app indeed is still running, but the searchfunction is failing for whatever reason. The reason I believe this is because when I add another route for haveibeenexploited.com/hello
, it works.